High-speed high-resolution digital-to-analog converters (DACs) are increasingly used for wired and wireless communication, direct digital synthesis and video signal processing. The main requirements of the DACs for these applications are high spectral-purity and small output errors. Trimming and calibration have been used to decrease element mismatches and result in high spurious-free dynamic ranges (SFDRs) and small maximum output errors. Alternatively, dynamic element matching (DEM) has been successfully applied to reduce the correlation of DAC noise to the input signal for achieving high SFDRs. For Nyquist-rate DACs, randomization is mostly used to suppress the harmonics. However, the possible maximum output errors of randomization are still large because the elements are selected randomly. Data weighted averaging (DWA), another DEM technique, is widely used for oversampling-rate ADCs and DACs. Random multiple data weighted averaging (RMDWA), one of the DWA-like techniques, was first proposed to be applied for Nyquist-rate DAC applications. With RMDWA, which has consecutive selection and randomization properties, the Nyquist-rate current-steering DAC structure can achieve both benefits of DEM techniques and proper layout switching schemes.
However, the increased switching activity of DWA-like techniques results in more dynamic errors. In order to keep the two properties and further decrease the switching activity, the present invention is proposed. The present invention proposes a new DEM technique suitable for the applications requiring high SFDR DACs. It is shown that harmonic distortions are suppressed with less switching activity.